US3681214A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing high-purity alkali hydroxides
Assignee: Grupul Industrial de Petrochimie
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Filing: 1971-01-11
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Granted: 1972-08-01
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Expires: 1991-01-11
Abstract
Abstract SOLUTION IS TREATED WITH AN AMALGAM OF THE SAME ALKALI METAL. THE AMALGAM IS PREFERABLY DRAWN FROM A MERCURYCELL ELECTROLYSIS PROCESS. A PROCESS FOR PRODUCING HIGH-PURITY ALKALI HYDROXIDES, E.G. SODIUM HYDROXIDE OR POTASSIUM HYDROXIDE IN WHICH AN IMPURE FLUID IS DRAWN FROM A DIAPHAGM-CELL ELECTROLYSIS PLANT AND A CONCENTRATION ABOVE 40% GENERALLY 50% OR HIGHER, IS DILUTED WITH DEIONIZED WATER TO A CONCENTRATION OF 20% TO 40% ALKALI HYDROXIDE, THE RESULTING SOLUTION BEING SUBJECTED TO ION EXCHANGE WITH A HIGHLY BASIC ANION-EXCHANGE RESIN WHEREUPON THE DECONTAMINATED
Inventors
- 👤 Teodor D Ionescu
- 👤 Gheorghe F Uta
- 👤 Aurel D Teodoru
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:50
CPC Classifications
C; C01; C01D; C01D1/00; C01D1/04; C01D1/28; C01D1/32
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |